During assembly of a tire onto a wheel, the exterior surface of the tire that comes into contact with the outer flange of the wheel is often wetted or “soaped” in order to enhance the seal that is obtained between the outer surface of the tire and the wheel. In order to ensure a proper seal to allow inflation of the tire, it is desirable to provide a substantially evenly wetted surface around the inboard and outboard sides of the tire. Previously, the soaping of the tire has been achieved both manually and automatically. Manual application of the soap or other liquid can be achieved by use of a brush, sponge, or sprayer. Automated methods have also used wetted brushes and/or sprayers. It is desirable in the art to provide a tire soaper that functions automatically to evenly distribute the soap on the inboard and outboard sides of the tire and that is capable of containing the excess soap for re-use.